Evaluation of Properties of Shotcrete Material for Underground Cavern for Hydro Power Project

In this paper described the determination of properties of shotcrete with steel fibers reinforcement, strictly as per ASTM standard method C 1018-89ε−1 (May 1990). The testing was done using closed- loop servo controlled electro-hydraulic ± 10t MTS system acquired under UNDP. This shotcrete was adopted by the Hindustan Construction Company, for use in underground caverns for Koyana Project. Using special MTS bend test fixture, the sawn beams with Dramix steel fibers were tested under third-point loading, applying constant rate of deflection of 0.05 mm per minute. The X–Y Recorder gave autographical record. From this record the point, deflection, strength and toughness at First-Crack are evaluated. Toughness Indices I5, I10, I20 and Residual Strength Factors R5, 10 and R10, 20 are determined. The performance of this shotcrete versus elastic, elastic–plastic, brittle material is indicated.